1. Field of the Invention
The present invention relates to recording apparatuses and recording methods related to disk rotation control, for example, in a case in which data is recorded into an optical disk.
2. Description of the Related Art
In these years, recordable optical disks such as compact disc recordables (CD-Rs) and rewritable optical disks such as compact disc rewritables (CD-RWs) have been spread. For these recordable optical disks (hereinafter called disks), recording methods, such as a packet-write method, a track-at-once method, a session-at-once method, and a disk-at-once method, are selected. Disks are rotated by constant-linear-velocity (CLV) control, in which a linear velocity is made constant, so that recording is performed at a constant linear velocity even at the inner-periphery side and the outer-periphery side of a recording area.
As disk driving control other than CLV control, there is also known constant-angular-velocity (CAV) control, in which an angular velocity is made constant.
Since a constant linear velocity is maintained in CLV control, recording can be performed in any position on a disk at the same data transmission rate. To this end, however, rotation driving control needs to be applied so as to obtain the rotation speed corresponding to a radial position on the disk. It takes time to change the number of revolutions. Therefore, when recording is performed with random access, for example, the number of revolutions needs to be changed in some cases and a long period elapses from the start of recording to the end.
In CAV control, since a constant rotation speed is maintained irrespective of a radial position on the disk, better accessibility is provided than in CLV control, but a recording speed is different depending on a recording position (the outer-periphery side or the inner-periphery side). Therefore, a data transmission rate is lower when recording is performed at the inner-periphery side than when recording is performed at the outer-periphery side.
It is demanded that an efficient recording operation be performed by selecting CLV control or CAV control according to the purpose of recording.